When I render my audio file with PowerCore plug-ins, the first section of the rendered file is muted. What is going on?
This is normal behaviour when using Steinberg Wavelab.
When you render something, the plug-ins that you use actually get instantiated again. The instantiation of the PowerCore plug-ins can take a little time, depending on the plug-in, which is why you see this muted part of the file.
The workaround is to leave a bit of silence in the beginning of the file. After rendering simply cut this part away.